The Nasdaq Composite (NASDAQINDEX:^IXIC) has performed extremely well in 2020, and investors in the top stocks that list on the exchange have been quite pleased with what they've seen. Even on a quiet day like Thursday, the Nasdaq managed to inch higher as of noon EST while other major stock market benchmarks gave up ground.

Yet three of the best performers in the Nasdaq-100 Index so far in 2020 don't always get the attention from U.S. investors that they deserve. That's because (NASDAQ:JD), MercadoLibre (NASDAQ:MELI), and Pinduoduo (NASDAQ:PDD) are foreign companies. Operating outside the U.S. hasn't done anything to hold these three Nasdaq-listed global companies back, but it does mean that those who concentrate largely on domestic stocks might have missed out.

A big rise for international Nasdaq stocks

The big winner in this group was Pinduoduo whose shares rose 23% as the Chinese e-commerce platform provider reported solid financial results in its most recent quarter. Those numbers included a 73% rise in gross merchandise value of goods listed on its e-commerce platform, along with an 89% rise in revenue and a 50% jump in monthly active users. Even more surprisingly, Pinduoduo posted an adjusted profit, reversing year-ago losses and showing that the company has been more efficient in targeting its growth toward more profitable opportunities than many investors had anticipated.

A dozen hands holding flags of various countries.

Image source: Getty Images.

The move adds to Pinduoduo's gains on Wednesday, which stemmed from the performance of larger companies in China's e-commerce space. Pinduoduo stock is up 257% so far in 2020. With the combination of the COVID-19 pandemic and the natural growth trajectory that e-commerce has enjoyed in the Chinese market, Pinduoduo finds itself well positioned to benefit from favorable trends for the foreseeable future.

That news was good enough to create carryover effects among Pinduoduo's Chinese peers. is one of them, and its stock rose another 7% Thursday at midday. JD has shown strong performance, with its stock price up 133% in 2020. Investors will have to wait until Monday, Nov. 16 to hear about JD's latest financial performance, but shareholders are optimistic that it will follow in the footsteps of its China e-commerce rivals despite some concerns about regulatory oversight.

Finally, MercadoLibre inched ahead by 2% on Thursday, bringing its year-to-date gains to around 150%. The Latin American online marketplace provider has benefited from resurgent e-commerce growth in its home territory, with COVID-19 outbreaks playing a key role in driving more shoppers online.

Some investors simply wanted to pick up shares of MercadoLibre on the cheap after a recent downturn that lopped off some of the excess from its stock price. However, there were also positive developments from the company on Thursday, as it announced that it will open new logistics hubs in southeastern Brazil to support its operations there. Brazil is a massive market for MercadoLibre, and the company is positioning itself to maintain its leadership role both there and throughout the Latin American market.

Let your portfolio travel for the best opportunities

It's understandable that many U.S. investors are reluctant to invest in foreign stocks. With different markets, different laws, different customer preferences, and different rules about disclosure and regulatory oversight, it can be more dangerous to invest in non-U.S. stocks.

Yet those who failed to see the potential of MercadoLibre,, and Pinduoduo have found themselves missing out on a big profit opportunity. By adding at least a modest allocation to international stocks  in your portfolio, you can cash in on these opportunities when they arise.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.